MRP Archives - Dumontis

Are You on the Way to Perfect Flow? (Part 3)

This is the third and last post in a series of three about knowing whether you are on your way to perfect flow. The better your flow, the more profitable your business will be and the more returns it will deliver. But how to know where you stand in terms of flow? And how to evaluate whether you progressed? This series of three post tries to develop two measures – flow velocity and flow smoothness – as the way to evaluate the level of and the progress towards flow. In this third post, I will focus on flow smoothness to complement the flow velocity measure discussed in the second post.
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Are You on the Way to Perfect Flow? (Part 2)

There are many approaches and methods that focus on improving flow. And for good reason, as improving flow yields improved profitability and returns. But how, in fact, can we determine our level of “flow”? In the first post, the typical ‘flow rate’ measure turned out to be unsuitable to do so. In this second post in a series of three, I therefore introduce flow velocity as a first measure to evaluate the level of and the progress towards flow.
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Are You on the Way to Perfect Flow? (Part 1)

There are many approaches and methods that focus on improving flow. Material Requirements Planning (MRP), Drum-Buffer-Rope (DBR) or Simplified-DBR (SDBR), Demand-Driven MRP (DDMRP), Quick Response Manufacturing (QRM) and of course Lean’s comprehensive Just-in-Time (JIT) approach share the same objective. In comparing these approaches, however, discussions often concentrate on their inner workings. But they often lack an operationalization of the concept of “flow” which they intend to improve. This series of three post tries to develop two measures – flow velocity and flow smoothness – as the way to evaluate the level of and the progress towards flow.
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Why Demand-Driven MRP (DDMRP) is Not Lean (Part 2)

Demand-Driven Material Requirements Planning, or DDMRP in short, promises to be the first real innovation to MRP since the invention of MRP. Furthermore, in one of its white papers, the Demand Driven Institute states that “Lean Finds a Friend in DDMRP” (2011). DDMRP is positioned as integrating Lean, the Theory of Constraints (TOC) as well as Six Sigma whilst fundamentally innovating the traditional MRP (and DRP) planning approach. What I think of it? Some parts are OK, but most of it still has nothing to do with Lean. In a series of two posts of which this is the second (the first can be found here), I’ll try to explain my views and hope this may help you and your company in making the right decision when looking at your values, your thinking, your philosophy and your strategies.
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Why Demand-Driven MRP (DDMRP) is Not Lean (Part 1)

Demand-Driven Material Requirements Planning, or DDMRP in short, promises to be the first real innovation to MRP since the invention of MRP. Furthermore, in one of its white papers, the Demand Driven Institute states that “Lean Finds a Friend in DDMRP” (2011). DDMRP is positioned as integrating Lean, the Theory of Constraints (TOC) as well as Six Sigma whilst fundamentally innovating the traditional MRP (and DRP) planning approach. What I think of it? Some parts are OK, but most of it still has nothing to do with Lean. In a series of two posts (the second one of this series you can find here), I’ll try to explain my views and hope this may help you and your company in making the right decision when looking at your values, your thinking, your philosophy and your strategies. (more…)

Kanban: the Lean Alternative to MRP

Let me just cut straight to the point: MRP and APS in the end simply don’t work. These approaches are based on what I call “the paradigm of the makeable reality”. They start from a large number of doubtful assumptions about this reality, like demand, inventory, bills-of-material, lot sizes, lead times, reject rates and capacity. And when these assumptions do not come to pass, it leads to nervousness and instability in the system. It’s time for something else. It’s time for an approach that accepts that reality isn’t manufacturable. (more…)